fixed to adapt gcc-5.4 & glibc-2.25

zhangmeng

2021-07-02 056f71f24cefaf88f2a93714c6678c03ed5f1e0e

 box/center.cpp

@@ -146,7 +146,7 @@
            replyer(reply);
            auto hosts = center->FindRemoteSubClients(pub.topic());
            for (auto &host : hosts) {
               tcp_proxy.Publish(host, kBHCenterPort, pub.SerializeAsString());
               tcp_proxy.Publish(host, kBHCenterPort, msg.content());
            }
         }
      };